Posted
by
Unknown Lameron Monday April 16, 2012 @08:07PM
from the nanosharks-with-lasers dept.

New submitter MTorrice writes "Scientists decorated red blood cells with gold nanoparticles so they could trigger the cells to dump their contents with a zap from a laser. The laser pulses heated the particles to produce nanopores in the cells' membranes. The cells contained two fluorescent dyes and both flooded through the pores and out of the cells after the laser pulses. Although the researchers studied the release of dyes, their end goal is to use red blood cells as a vehicle for drug delivery, because the cells are naturally compatible with the immune system and circulate for days in the body. Until now, researchers have found easy ways to load the cells with drugs, but the challenge has been to control the molecules' release."

Interesting, but not at all. Sunshine wouldn't warm the particles enough to perforate the cell. Secondly, and more importantly, if you suddenly dumped a lethal load of drugs inside red blood cells, the person would die 100-120 days later when the lifecycle of those blood cells came to an end. The only way to do what you suggest would be to keep inserting a small quantity daily, so that no single subset of red cells would cause a lethal dose when the cells expire, but allowed for a trigger to release them al

It seems to me this would be best used to get drugs delivered deep within the body, such as in a tumor, without dosing the rest of the body, or even near by areas.

But how do they get the laser there? If it were near the surface, a laser could be used. But deeper in the body, liver, brain, etc., how do you get laser light in there to cause the drug bomb to be dropped?

Quoting TFA:

Mario Magnani, of the University of Urbino, in Italy, calls the method novel and interesting, especially because it appears to leave the red blood cells intact. However, he sees two practical problems: Infrared light doesn’t penetrate deeply into body tissue, making many tumors difficult to access with the technique’s laser.

Wouldn't intersecting focused microwaves [technologyreview.com] be a better approach for heating these blood cells than an infrared laser?

But how do they get the laser there? If it were near the surface, a laser could be used. But deeper in the body, liver, brain, etc., how do you get laser light in there to cause the drug bomb to be dropped?

But how do they get the laser there? If it were near the surface, a laser could be used. But deeper in the body, liver, brain, etc., how do you get laser light in there to cause the drug bomb to be dropped?

It's been a while since I studied optical therapy (before dropping out a PhD program in medical biophysics), but I'm pretty sure I remember that you can use fiber-optics. I think it's relatively "easy" (and not too invasive) to poke the patient with a fine fiber-optic cable (guided by ultrasound, I suppose) that delivers the laser light at the target site. In theory, I suppose they might be able to leave the fiber-optics in the patient for a while to deliver treatment over a few days/weeks (like a sort of "optical catheter").

Now, I only had about four weeks of classes on optical therapy 6 years ago (as part of a course that also covered thermal and radiation therapies), so I'm only barely more qualified to write on the subject than most anonymous internet jackasses. That said, I do have a clear memory of slides from class with patients with fiber-optic cables poking into their heads or other parts of their bodies, so I remember that it can be done.

I'll admit, I have yet to RTFA, but Gold itself is believed to be beneficial in the treatment of Rheumatoid Arthritis, so who is to say it isn't the reason they are experiencing gains using it as an assisted delivery mechanism....

It's easier to make/process, use and analyze nanoparticles of gold than anything else, so it's the best characterized material. It's easiest to process and analyze because it's heavy and inert. And then for medical uses it's key that gold tends to remain nontoxic in any particle size/shape unlike most other nontoxic metals. Silver is not as good about being totally nontoxic in any formulation like gold, though interestingly sizing of silver nanoparticles show deposition in different tissues based on size (s

By crossing two or more electromagnetic beams, each of which is of insufficient strength to stimulate the reaction,can one focus the drug's release at the point where they intersect if the combined energy exceeds the required threshold?

This is really cool! My family and I just learned about this from a researcher at the Cincinnati Museum a week ago. They were holding their "Nano Days" event, and this was one of the booths. It turns out that a solution containing gold nano particles in a small enough amount is actually red. She explained the same concepts used in the article, and how gold nano particles can be used to target cancer cells, bind to them, and release a dose of cancel-killing drugs (similar to current chemotherapy) with a